A game spinner has regions that are numbered 1 through 8. If the spinner is used twice, what is the probability that the first number is a 3 and the second is a 5?

A. [tex]\frac{1}{8}[/tex]

B. [tex]\frac{5}{32}[/tex]

C. [tex]\frac{1}{64}[/tex]

D. [tex]\frac{1}{16}[/tex]



Answer :

To determine the probability of spinning specific numbers in two spins, we need to follow these steps:

1. Probability of the first event (spinning a 3):
- Since the spinner has 8 evenly divided regions, each numbered from 1 to 8, the probability of landing on any specific number in one spin is [tex]\(\frac{1}{8}\)[/tex]. Therefore, the probability of spinning a 3 on the first spin is [tex]\(\frac{1}{8}\)[/tex].

2. Probability of the second event (spinning a 5 after the first spin was a 3):
- The second spin is independent of the first spin, meaning the outcome of the first spin does not affect the second. Thus, the probability of spinning a 5 on the second spin is also [tex]\(\frac{1}{8}\)[/tex].

3. Combined probability of both events occurring in sequence:
- To find the probability of both events happening (first spinning a 3 and then spinning a 5), we multiply the probabilities of each independent event:
[tex]\[ \text{Probability of getting a 3 and then a 5} = \left(\frac{1}{8}\right) \times \left(\frac{1}{8}\right) \][/tex]
- Calculating this gives:
[tex]\[ \frac{1}{8} \times \frac{1}{8} = \frac{1}{64} \][/tex]

Therefore, the probability that the first number is a 3 and the second is a 5 is [tex]\(\frac{1}{64}\)[/tex], which corresponds to option C.